1. Field of the Invention
This invention relates to devices for use in the rapid cooling of fluids in various containers, and more particularly to such devices suitable for cooling large quantities of extremely hot liquids such as soups, stocks, sauces, and the like, especially in a commercial kitchen.
2. Description of the Related Art
In the food preparation industry, kitchens create stock to be used in gravy, soups, and other foods served along with meals. The stock is made by cooking meat, bones, fat in water to a temperature of 190° Fahrenheit to both pasteurize and allow the heated water to absorb the fat. It is currently common practice to create between 1 and 100 gallons of stock and let it sit in an open pot. The pot is usually stored in either a kitchen sink or a refrigerator/freezer. Often, as the stock is cooling off, airborne contaminants may enter the stock creating a safety and health hazard in the kitchen and ultimately to the consumer. Bacteria also grows extremely rapidly in the temperature range between 140° and 41° F., often doubling every 20 minutes in this temperature range. The stock often takes between 1 to 7 hours to chill depending on the quantity and method of chilling.
There are several conventional methods of chilling stock. A common method is simply to place the stock into a refrigerator. Given that it takes two hours to chill 12 oz. of liquid in this manner, chilling a commercial quantity of stock in this manner requires an extremely long time (several hours, depending on the quantity to be chilled) to bring the stock down to a safe temperature of 40° F., and it often puts considerable strain on the refrigerator, raises the temperature of the refrigerator, and thus threatens the safety of all the food stored therein. Refrigerators are ill-served for this practice because they are not designed to chill hot food quickly (they are simply designed to keep cold food cold). Even food that is chilled in ambient air to room temperature (˜70° F.) and then placed in a refrigerator will still require a lot more chilling time to get to 40° F. The process may be accelerated by chilling the food in an ice water bath and then placing it into a refrigerator, however this will still take at least two hours and require a very large ice water bath to accommodate large quantities of food.
One conventional method that is slightly better than those mentioned above is to pour the stock/food into one gallon bags, place the bags into a cold water bath for at least an hour, and then place the bags into a refrigerator. Even so, there are drawback to this method, as it still takes too long and results in many individual units of stock/food that cannot be stored in a space-efficient manner (owing to the lack of a discrete shape to the bag). Also, the cold water bath temperature rises precipitously and the compressor is not strong enough to keep up with the rising temperature. As such, it is frequently necessary to add ice to the cold water bath.
Another conventional way to hasten the cooling of such liquids is the use of a cold paddle or ice paddle such as that described in U.S. Pat. No. 5,058,396 to Faiola. Typically, a plastic wand or paddle having one or more projections is filled with a cooling medium such as water, cooled or frozen in a refrigerator or freezer, and inserted into and stirred within the hot stock/food to hasten the cooling of the stock/food. There are many problems with such a device. First, the paddle must be inserted and stirred manually, which requires great effort on the part of the stirrer. Also, the stirrer must be positioned substantially right over or in front of the open vat of stock, which is an excellent way of communicating bacteria from the stirrer to the food. Additionally, the paddle is made of a lightweight material such as plastic to make it easy to handle, however plastic is not an exceptionally efficient transmitter of heat (i.e., it has good insulative properties). The paddle itself may also be contaminated with bacteria or traces of other foods into which it had previously been dipped, thereby directly introducing bacteria, allergens, or other undesirable foreign agents into the food.
Other conventional methods include using a device called a “blast chiller”, which is essentially a very powerful refrigerator. Typical blast chillers are manufactured by the Traulsen company of Fort Worth, Tex. However, a typical blast chiller will still take 90 minutes to cool 24 gallons of food from 135° F. to 40° F. Such a device would require about 2½ hours to cool 24 gallons of food from 190° F. to 40° F. and does not really benefit the commercial kitchen that generates up to 100 gallons of food at a time.
Another existing device is called a tumble chiller which resembles an extremely large washing machine. It consists of a 4-5 foot diameter rotating drum disposed within an even larger water bath, and it accepts 4-8 quart bags of food. The food bags are sloshed around in the drum until cool. Typical tumble chillers are manufactured by the Cleveland Range company of Cleveland, Ohio. There are several disadvantages to the tumble chiller. First, it occupies an enormous amount of space. Second, it requires a large number of very small bags of material to be cooled. Third, because the bags flop around within the rotating drum, there is a significant chance of breakage. Additionally, when the bags are removed, because they have no discernible shape, they are difficult to stack and store.
Devices exist to chill beverages from room temperature to about 40° F., such as those described in described in U.S. Pat. No. 4,580,405 to Cretemeyer, III (which works poorly) and U.S. Pat. No. 5,505,054 to Loibl et al. (which works exceptionally quickly and efficiently), the teachings of which are incorporated by reference herein. Yet the prior Loibl device, while extremely effective for beverages at room temperature is incapable of cooling extremely large quantities of extremely hot liquids. Also, the Loibl device typically depends on the beverage coming in its own container, be it a 12 oz. aluminum can, a 16-20 oz. glass or plastic bottle, or the like.
Accordingly, there is a long-felt need to provide a system and device for rapidly cooling and subsequent storing of large quantities of extremely hot liquids such as commercially prepared stocks, soups, sauces, gravies, and the like.